Los Angeles , California -LRB- CNN -RRB- -- Dr. Conrad Murray , personal physician to Michael Jackson , was charged Monday with involuntary manslaughter in connection with the pop star 's death last summer .

A criminal complaint filed earlier in the day alleged that Murray `` did unlawfully , and without malice , kill Michael Joseph Jackson . ''

Murray turned himself in shortly before 4 p.m. at a branch courthouse near Los Angeles International Airport . He pleaded not guilty during a brief hearing before Judge Keith L. Schwartz .

The judge set bail at $ 75,000 , despite arguments from prosecutor David Walgren that Murray is a flight risk .

The judge refused to suspend Murray 's medical license as a term of his bond , but he did order him not to use any anesthesia on patients .

`` I do n't want you sedating people , '' Schwartz told Murray .

Read the criminal complaint

The involuntary manslaughter charge means that Murray caused Jackson 's death by acting `` without due caution and circumspection . ''

If convicted , Murray would face a maximum four-year prison sentence , according to prosecutors .

More on involuntary manslaughter

Members of Michael Jackson 's family -- including his parents Joe and Katherine Jackson , sister La Toya Jackson , and brothers Jackie , Jermaine , Randy and Tito Jackson -- attended the hearing .

`` Not enough , '' Jermaine Jackson said when asked what he thought of the charge .

`` I do n't like what happened , '' Joe Jackson said as he left the courthouse .

La Toya Jackson later issued a statement through a publicist .

`` Michael was murdered and although he died at the hands of Dr. Conrad Murray , I believe Dr. Murray was a part of a much larger plan , '' her statement said . `` There are other individuals involved and I will not rest and I will continue to fight until all of the proper individuals are brought forth and justice is served . ''

Her statement did not elaborate on what she meant in her reference to `` a much larger plan . ''

Murray traveled to Los Angeles at the end of January from his home in Houston , Texas , in expectation of possible charges , his lawyer said .

He used part of his time last week to visit the pop star 's resting place in the Forest Lawn Memorial Park in Glendale , California .

Murray , a cardiologist , was hired as Jackson 's personal physician last spring as the singer prepared for comeback concerts in London , England .

The doctor told Los Angeles police that he was with Jackson at his $ 100,000-a-month rented Holmby Hills mansion through the early morning hours of June 25 , 2009 , in an effort to help the pop star fall asleep , according to a police affidavit .

He administered sleep aids , and after Jackson finally began sleeping in the late morning hours , Murray said , he left the bedroom for `` about two minutes maximum , '' the affidavit says .

`` Upon his return , Murray noticed that Jackson was no longer breathing , '' it says .

The doctor stayed with Jackson as an ambulance rushed him to UCLA Medical Center .

Efforts at CPR proved fruitless , and Jackson was pronounced dead at 2:26 p.m. .

The Los Angeles County coroner ruled Jackson 's death a homicide , resulting from a combination of drugs , primarily propofol and lorazepam .

The coroner 's statement said Jackson died from `` acute propofol intoxication , '' but there were `` other conditions contributing to death : benzodiazepine effect . '' Lorazepam and two other drugs Murray said he used are benzodiazepines .

The doctor told investigators he had given Jackson three anti-anxiety drugs to help him sleep in the hours before he stopped breathing , a police affidavit said .

Murray had been treating Jackson for insomnia for six weeks at the time of the singer 's death . The doctor told investigators he gave Jackson 50 milligrams of propofol , the generic name for Diprivan , diluted with the anesthetic lidocaine every night via an intravenous drip .

The doctor told police he was worried that Jackson was becoming addicted to the drug and tried to wean him off it .

During the two nights before Jackson 's death , Murray said , he put together combinations of other drugs that succeeded in helping Jackson sleep .

The full autopsy report , which was released Monday afternoon , included an analysis by an anesthesiology consultant of the use of propofol .

The consultant , Dr. Selma Calmes , concluded that the `` standard of care for administering propofol was not met . ''

`` There was no evidence of an infusion pump for control of an IV infusion . No monitors were found at the scene ; a blood pressure cuff and portable pulse oximeter were recovered from a closet in the next room , '' Calmes wrote .

An oxygen tank was found near where Jackson slept , but it was empty when the coroner investigator checked it two weeks after Jackson died , Calmes said .

`` Multiple opened bottles of propofol were found with small amounts of remaining drugs , '' Calmes said . `` A used bottle should be discarded six hours after opening , to avoid possible bacterial growth . ''

`` The level of propofol found on toxicology exam are similar to those found during general anesthesia for major surgery , '' Calmes said .

During such surgery , any patient would be `` intubated and ventilated by an anesthesiologist , '' she said .

The consultant 's report said that the level of lorazepam found in Jackson `` would have accentuated the respiratory and cardiovascular depression from propofol . ''

CNN 's Ted Rowlands contributed to this report .

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NEW : Charge `` not enough , '' says Michael Jackson 's brother Jermaine

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DA 's office in L.A. files complaint alleging single count of involuntary manslaughter

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Dr. Conrad Murray was Jackson 's physician when the singer died on June 25

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Jackson 's father , Joe Jackson , will discuss the case tonight at 9 ET on `` Larry King Live ''